Amnesty International has called for a full and impartial investigation into the bloodshed in Egypt.
The international body said that the authorities' response to the protests has been 'grossly disproportionate'.
According to news.com.au, the London-based human rights organisation also appealed for United Nations experts to be allowed to investigate the crackdown.
Egypt's ousted president Mohamed Morsi's supporters have pledged to stage daily demonstrations.
Security forces besieged a Cairo mosque full of Islamist protesters after a day of clashes on Friday that left more than 80 dead, the report added.